# A one-number triage tool for C code (and a cheap feedback loop for LLM output)

> Source: <https://dev.to/jens_harms_c50ccbd4550050/a-one-number-triage-tool-for-c-code-and-a-cheap-feedback-loop-for-llm-output-1eco>
> Published: 2026-09-20 12:48:39+00:00

C gets hard to trust in three predictable ways: deep nesting, pointers to

pointers, and `a->b->c` chains where nobody null-checks the middle pointer.

So I wrote a tiny scorer that squashes that into one number per function:

```
score(f) = nesting × pointer depth × deref chain
```

Each factor is one sentence:

`if`/` for`/` while` levels`int *`, `int **`, `int ***` in params and locals (deeper is closer to a memory bug)`a->b->c` runs, i.e. null-derefs where the middle pointer came from somewhere else
It's one file, zero dependencies, no parser worth mentioning.

I checked it against maintenance churn — how often a function actually gets

touched — on two very different codebases (libXt, a 40-year-old X11 toolkit,

and libtiff, a format parser):

I also ran it across 20+ years of git history for libtiff, curl, redis and

OpenMotif. None of them trend toward smaller functions — the median stays flat

and **the biggest function only ever grows**. Which is exactly why a cheap pointer

to the hot spots helps.

LLM-generated C has the same tell. The loop is:

```
generate → c-score file.c → "rewrite the top 3" → re-score
```

One round visibly flattens the output. A dumb, explainable number is enough to

steer an LLM — you don't need a real static analyzer for this.

It's a triage tool, not a bug detector. It won't find semantic bugs, and it

can't see a deep call stack full of side effects. The parser is not perfect,

and the Python is LLM-generated too. But the idea is the sound part — before

you pick it apart, run it on a real codebase.

```
pip install c-code-score
for f in src/*.c; do c-score "$f"; done \
  | awk '/^[^ ]/{n=$1} /^  score:/{print n,$2}' \
  | sort -k2 -rn | head
```

Repo: [https://github.com/xtforever/c-score](https://github.com/xtforever/c-score) · [https://codeberg.org/au1064/c-score](https://codeberg.org/au1064/c-score)